Pitch and Frequency
The relationship between the speed of sound, its frequency, and wavelength is But the music from all instruments arrives in cadence independent of Gently blow air near the edge of the bottom of the sheet and note how the sheet moves. Describe the relationship between the speed of sound, its frequency, and its of a musical instrument is directly related to the wavelengths of sound it produces. . Gently blow near the edge of the bottom of the sheet and note how the sheet. The amplitudes of the overtones relative to the fundamental give the note its quality . Music is composed of sounds with a fundamental frequency and overtones. . The relationship between these should be obvious — two semitone intervals.
Let's look at some more examples. A flute is essentially a tube that is open at both ends. Air is blown across one end and sound comes out the other.
Music & Noise – The Physics Hypertextbook
A spectral analysis confirms this. Note how the second harmonic is nearly as intense as the fundamental.3. What is the difference between a Noise and a Note?
This strong second harmonic is part of what makes a flute sound like a flute. A recorder is also a tube with two open ends. It produces a sound similar to a flute, but not exactly the same.
This nearly missing second harmonic is part of what makes a recorder sound like a recorder and not sound like a flute. A tuning fork is forked; that is to say, it splits from its handle into two branches called tines.
Each tine is fixed to the handle at one end, but is free to vibrate at the other. As a result, one would expect to find only those harmonics that were odd multiples of the fundamental in the spectrum of a tuning fork.
This is what the spectral analysis shows. The even harmonics are present, but are they are weak and are probably due to the sympathetic vibrations of something nearby. This spectra was produced by striking a large, demonstration-size tuning fork not the one pictured above with an excessively heavy blow. Tuning forks should always be tapped lightly and on a resilient surface. Doing so reduces the intensity of the "ping" overtones, which is a desirable thing. As discussed in an earlier unitthe frequency is simply the reciprocal of the period.
For this reason, a sound wave with a high frequency would correspond to a pressure time plot with a small period - that is, a plot corresponding to a small amount of time between successive high pressure points. Conversely, a sound wave with a low frequency would correspond to a pressure time plot with a large period - that is, a plot corresponding to a large amount of time between successive high pressure points. The diagram below shows two pressure-time plots, one corresponding to a high frequency and the other to a low frequency.
Frequency, Pitch and Human Perception The ears of a human and other animals are sensitive detectors capable of detecting the fluctuations in air pressure that impinge upon the eardrum. The mechanics of the ear's detection ability will be discussed later in this lesson. For now, it is sufficient to say that the human ear is capable of detecting sound waves with a wide range of frequencies, ranging between approximately 20 Hz to 20 Hz. Any sound with a frequency below the audible range of hearing i.
Humans are not alone in their ability to detect a wide range of frequencies. Dogs can detect frequencies as low as approximately 50 Hz and as high as 45 Hz. Cats can detect frequencies as low as approximately 45 Hz and as high as 85 Hz. Bats, being nocturnal creature, must rely on sound echolocation for navigation and hunting.
Bats can detect frequencies as high as Hz. Dolphins can detect frequencies as high as Hz.
Music & Noise
While dogs, cats, bats, and dolphins have an unusual ability to detect ultrasound, an elephant possesses the unusual ability to detect infrasound, having an audible range from approximately 5 Hz to approximately 10 Hz.
The sensation of a frequency is commonly referred to as the pitch of a sound. A high pitch sound corresponds to a high frequency sound wave and a low pitch sound corresponds to a low frequency sound wave.
Amazingly, many people, especially those who have been musically trained, are capable of detecting a difference in frequency between two separate sounds that is as little as 2 Hz. When two sounds with a frequency difference of greater than 7 Hz are played simultaneously, most people are capable of detecting the presence of a complex wave pattern resulting from the interference and superposition of the two sound waves.
Certain sound waves when played and heard simultaneously will produce a particularly pleasant sensation when heard, are said to be consonant. Such sound waves form the basis of intervals in music. For example, any two sounds whose frequencies make a 2: That is, two sound waves sound good when played together if one sound has twice the frequency of the other.